U.S. Pat. No. 2,657,195 broadly discloses polyesters of various stilbenedicarboxylic acid isomers with glycols, aminoalcohols, and diamines. Various glycols are disclosed containing 2 to 16 carbon atoms, but copolyesters of 1,6-hexanediol and 1,4-butanediol are not specifically disclosed.
U.S. Pat. No. 3,496,839 relates to low molecular weight homopolymers of 4,4'-stilbenedicarboxylic acid and aliphatic glycols useful in radiation-cured crosslinked polyester coatings. 1,6-Hexanediol and 1,4-butanediol are disclosed in column 2, lines 20 to 44, in a general listing of the glycols useful in these coatings. No examples are given using a combination of butanediol and hexanediol. Neither U.S. Pat. No. 2,657,195 nor U.S. Pat. No. 3,496,839 distinguishes one stilbenedicarboxylic acid isomer from another, i.e., 4,4'- from 3,3'- or cis- from trans-, etc.
Our own U.S. Pat. No. 4,420,607 (issued Dec. 13, 1983), U.S. Pat. No. 4,459,402 (issued Feb. 10, 1984), U.S. Pat. No. 4,468,510 (issued Aug. 28, 1984), U.S. Pat. No. 4,526,822 (issued July 2, 1985) all disclose polyesters based on trans-4,4'-stilbenedicarboxylic acid using various glycols which include 1,6-hexanediol and 1,4-butanediol. No examples of copolyesters based on these glycols are specifically disclosed.
Our U.S. Pat. No. 4,551,520 discloses copolyesters based on terephthalic acid, trans-4,4'-stilbenedicarboxylic acid and 1,4-cyclohexanedimethanol.
Other patents which disclose trans-4,4'-stilbenedicarboxylic acid are Japanese Kokai 72348/74, and U.S. Pat. Nos. 2,657,194, 3,190,174, 3,247,043, 3,842,040, 3,842,041, and 4,073,777. Polyesters of trans-4,4'-stilbenedicarboxylic acid and neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, and 1,10-decanediol are disclosed by Meurisse, et al., in the British Polymer Journal, Vol. 13, 1981, page 57 (Table 1). Jackson and Morris disclose homopolyesters from trans-4,4'-stilbenedicarboxylic acid and various aliphatic glycols in the Journal of Applied Polymer Science, Applied Polymer Symposia, 41, 307-326(1985). Our copending applications filed of even date herewith entitled, "Polyesters of trans-4,4'-Stilbenedicarboxylic Acid, 1,6-Hexanediol, and 1,4-Cyclohexanedimethanol" and "Polyesters of trans-4,4'-Stilbenedicarboxylic Acid, 1,4-Butanediol, and Ethylene Glycol" also disclose polyesters based on trans-4,4'-stilbenedicarboxylic acid. No examples of copolyesters based on these 1,4-butanediol and 1,6-hexanediol are specifically disclosed.